Developing apparatus with tubular gas discharge



May 27, 1930. A. LANGSNER 1 1,760,149

DEVELOPING APPARATUS WITH TUBULAR GAS DISCHARGE A. LANGSNER May 27,1930.

`DEVELOPING APPAIRATUS WlTH TUBULAR GAS DISCHARGE Filed Jan. 13, 1928 3Sheets-Sheet 2 May 27, 1930. A. LANGSNER 1,760,149

DEVELOPING APPARATUS WITH TUBULAR GAS DISCHARGE Filed Jan. 13, 1928 3Sheets-Sheet 5 Patented May 27,1930

UNITED STATES- PATENT' OFFICE ADOLPH LANGSNER, 0F CHICAGO, ILLINOIS,ASSIGNOR T0 EUGENE DIETZGEN COM- PANY, OF CHICAGO, ILLINOIS, ACORPORATION OF DELAWARE DEVELOPING APPARATUS WITH TUBULAR GAS DISCHARGEApplication led January 13, 1928.l Serial No. 246,460.

My invention relates to apparatus for developing light sensitivematerial, such for instance, as paper, by the action of an alkalinedeveloping gas, such for instance, as ammonla gas.

One of the objects of my invention is to provide a compact cabinet typeof device in which the sheets or continuous strips of the lightsensitive material are fed through the cabinet and wherein `they aresubjected to the action of the developing gas in a manner to develop thesheets or strips in a minimum time and travel, and wherein also, thesheets are passed through a Ventilating chamber within the cabinet toremove the occluded gases from the paper before discharging the sameoutside of the cabinet.

Another object of my invention resides in providing a developingapparatus of the above type, wherein the developing gas is projectedagainst one of the traveling carriers which feed the light sensitivematerial, or paper, through the cabinet. An ancillary object of thisfeature of my invention resides in the utilization of a tubularvalve-like construction which may be opened and closed and regulatedwhereby it controls the amount of developing gas projected against thefeeding mechanism, or against the light sensitive material itself, ifIdesired, and by which means the control and flow-of the gas is at alltimes effected from a convenient point outside of the cabinet and in amanner such that the operator will not be subjected to the injuriousaction of the developing gases during the operation of the machine.

Still another object of my invention re'- sides in a novel arrangementof receptacle or cradle into which the developed paper is discharged asit is fed from the machine and which cradle is constructed and arrangedto assist in removing the occluded gases from the discharged paperwhereby the ammonia gases are not liberated to the atmosphere andwhereby practically all traces of the ammonia gas are effectivelyremoved from the developed paper.

Still another object of my invention esides in the provision of improvedmeans for releasing the blanket from the cylinder roll and in the meansfor adjusting thetension of the blanket at either longitudinal edge tokeep the blanket and cylinder in alignment.

Fig. 2 is a plan view taken on line 2 2 of Fig. 1. L

Fig. 3 is a section taken on line 3-3 of Fig. 1.

Fig. 4 isa view of a modified form of the construction shown in Fig. l.

Fig. 5 is a section on line 5 5 of Fig. 1.

Fig. 6 and 7, are sectional views taken on line 6-6 of Fig. 5, (showingdiierent posia tions of the gas valve.

Fig. 8 is a view showing modified manner in which blanket and cylindermay be released for adjusting the light sensitive material, and Fig. 9is still another modification of such an arrangement.

In general, in the preferred form of my invention herein enclosed, Iprovide an enclosing cabinet arranged to form a develop* ing chamberproper and a connected ventilating chamber together with means,preferably power driven, for feeding either sheets or continuous stripsof light sensitive material, such as paper, from the entrance to thedeveloping cabinet, through the developing chamber, thence in andthrough the ventilating chamber and thence out of the machine into adischarge receptacle of especial construction. During the travel of thelight Sensitive material through the developing chamber by means oftraveling feed carriers, I subject the material to a stream or jet ofammonia as which is projected on to the surface cfg the carrier througha tubular rotatable valve, and in addition, this rotatable carrier isprovided with a slightly porous surface adapted to hold the gasesoccluded therein, whereby throughtheir contact with the light sensitivematerial a greater and more effective developing action is secured asthe paper is fed along;

Referring now to t e drawings in detail;i

terial either in sheet form or in the form ofl I provide an enclosingcabinet 2, preferably mounted on legs or standards 4, and the cabinet isformed with' a horizontal partition 6, to provide a lower developingchamber 8, and an upper Ventilating chamber 10. Beneath the base lof thedeveloping chamber I mount a prime mover, such as a motor, adapted todrlve a shaft 12, on which is mounted a worm 14, meshing with worm gear16, .on ashaft 18, which in turn carries a sprocket wheel 20 meshingwith a chain 22. Within the ventilating chamber I provide a suitablesupport or bracket 24, and upon this I mount the means for feeding thelight sensitive material into, through, and outside of the developingchamber. `In the present instance, this feeding means comprises tworelatively moving traveling carriers, viz., a relatively large cylinder26, and a continuous blanket 28. The cylinder is mounted on a shaft 30in the bearing or support 24, while the blanket is adapted to passaround a series of guide rolls 32, 34, and 36. The guide roll 32 islocated at theuppermost part of the developing chamber 8 adjacent to theupper portion of the cylinder 26. Guide roll 36 is located at the frontof the developing chamber beneath-the cylinder 26 and ad] acent to theinlet opening 38 of the cabinet. Guide roll 34 is mou/nte on a bellcrank lever 40 pivotally mounted as at'42, on the bracket 24. Theconstruction and o eration of this bell crank lever will be laterescribed. As shown, blanket 28 is thus arranged to pass peripherallyabout the rearmo'st half of the cylinder 26 and in firm contact withsaid cylinder. Sprocket chain 22 passes over a sprocket 42 on the feedroll 36, and thereby serves to drive this feed roll, and hence to causethe blanket to travel into the continuous path illustrated. In a similarmanner, by reason of the peripheral contact of the blanket with thecylinder 26, the cylinder also is rotated. The light sensitive maacontinuous strip is introduced throuvh the lopening 38, being pushedacross a ledge or bracket 44, and beneath a felt or rubber packing orgasket 46 attached to the inner wall of the cabinet, and which gasketserves to prevent the escape of the developing gas through the inletopenin 38. As the innermost end of the light sensitive material is fedthrough openin 38, it is directed by any suitable deflector into thebite formed by the traveling blanket 28 and the rotating cylinder 26where the material is carried around between the blanket and thecylinder to a point in the present construction beneath the feed roll32,

where it is discharged between two deflectors 48 and 50 located at themouth of the entrance between the developing and ventilat- 7it isconstructed as a rotatable sleeve valve comprising an outer rotatabletubular sleeve 52 embracing an inner stationary tubular member 54mounted to the casing 2. The sleeve 52 is journaled on the member 54,and being hollow, the innermost tube 54 is connected by means of anipple 56 with a flexible tube 58, connecting with any source of ammoniagas, preferably under controlled pressure. In addition, the inner andouter sleeves 52 and 54 are provided with slots 60 and 62 which extend,preferably, the length of the tubular valves, which length is suiicientto accommodate sheets or strips of light sensitive material of a maximumwidth. In addition, the outer tube'52 is provided with an arcuatebracket 64 riveted thereto as at 66, which bracket is provided-With ahandle 68 for turning the outer casing, whereby when such handle isturned annularly, the slots and 62 will be made to open or close more orless and thereby control the fine streamor sheet of developinggas whichis projected from the valve. Obviously, by rotating the valve farenough, the discharge of gas will be wholly cut off or will be opened toits maximum amount. The advantage of such construction resides in theability to control from the exterior of the cabinet the discharge of thegas within the interior developing chamber, whereby the operator willnot be subjected to the injurious action of this ammonia. gas when thedeveloping action is not needed.

In the form of my invention in Fig. 1 of the drawings, this gasdischarge valve is i1- lustrated as being locatediin suitable .bearings70 and 72 immediately beneath the lowermost part of travel of theblanket 28, whereas in Fig. 4 of the drawings it is located'immediatelybeneath the large cylinder which constitutes a part `of the feedingmeans. In the rst instance, the blanket itself is formed of rubberizedfabric, or any other material provided with a porous surface adapted tohold the developing gas in occlusion therein; for instance, the blanketmay be rprovided with a relatively soft rubber surface which is slightlyporous, and when the ammonia gases are discharged'directly into contactwith this traveling blanket the ases will be retained in the pores sothat as t e blanket is fed along and comes intodirect contact with thelight sensitive material, such as paper, it will provide a moreeffective and intimate developing action, especially so since the' gasesare retained within this rubber surface and between the light sensitivematerial and the surface of the cylinder.

In the construction wherein I project the gas directly into contact withthe cylinder itself, then of course the cylinder is provided with such aporous surface; in some instances it is Within the contemplation of myinvention to arrange this tubular valve so'as to discharge directly uponthe sheets or strips of light sensitive material just before they passbetween the traveling carriers; however, I prefer the constructionsillustrated.

I preferably provide the handle 68 of the valve with the locking devicefor holding it in any desired position. To this end, the support 2(Figure 3) is provided with a bracket 74, formed with a step-likesurface, con sisting of a plurality of notches 76, into which thishandle 68 may be pressed so as to hold it in the adjusted position.

In the modification shown in Fig. 4 of the dra-Wings, the cabinet 76 isprovided with an interior bracket 78 on which the cylinder 80 is mountedas on a central shaft 82. In this instance, the gas projecting valve 84,is shown as mounted immediately beneath the cylinder, and the blanket 86is mounted to pass around suitable guide rolls 88, 90 and 92. In thisinstance, the central shaft 82 is provided with asprocket 94, driven bya chain 96 from another sprocket shaft 98 on the motor driven shaft 100,and the front opening of the cabinet is provided with a shelf 104 alongwhich the light sensitive material may be passed through the opening 102and by the packing 106 into contact with a curved deiector 108, mountedadjacent to the guide roll 88, so that the light sensitive material isforced into position between the cylinder and the blanket 86. l It willbe noted that in this instance the cylinder is directly. rotated by asource of power and serves by contact with the blanket 86, also to causethe latter to travel to effect the feeding movement of the lightsensitive material into and through discharged deflectors 108 and 110positioned between thex developing chamber 112 and Ventilating chamber114. In addition, the roll is ad- ]ustably mounted on an arm 116,adjustably held by ai wing nut 118 so as to adjustably take up the slackin the blanket or cords 86.

The Ventilating chamber 10 shown in Fig. 1 is provided with a series ofguide rolls 120, 122, 124, 126, 128, 130, 132, 134 and 136, about whichpass two travelling blankets or series of cords; in the latter case,ythe rollers are grooved so as to hold the cords from literaldisplacement. @ne set of cords, or the blanket 138, is adapted to travelfor a good part of its length directly in contact with another set ofcords or'blanket 140; in other words, the two sets of cords or blanketstravel together from a point between the entering guide rolls 134 and136 located at the junction of the developing chamber 8 and theVentilating chamber 10, upwardlyaround the guide roll 26, thence aroundthe guide roll 122, thence downwardly to a point between the guide rollsand 132, where the blanket 138 or cords passes upwardly by itself aroundthe guide rolls 124 and 120, thence downwardly around guide roll 128 andthence back to guide roll 134. In the saine way, the

blanket or cords 140 passes by itself from` the guide roll 132 to guideroll 136, and all the rest of the time it is travelling in contact withthe other set of cords or blanket. By this arrangement when the lightsensitive sheets or strips of material or paper are discharged throughthe deflectors 48 from the developing chamber, the developed materialwill thus pass between the cords or blanks and will be carried about intortuous or circuitous paths about the Ventilating chamber where theoccluded gases in the material will be subjected to the action of themoving column of air which enters through an opening 142 and sucked outof the chamber 10 by means of a suction fan 144. These belts, blankets,or cords which pass around the several guide rollers are driven by meansof a sprocket chain 146 passing over a sprocket gear 148, on shaft 150,on which the guide roller 134 is mounted, and this chain 146 is in turndriven from the sprocket 42 in the developing cham; ber.

ln the form of my invention illustrated in Fig. 4, a somewhat similararrangement of cords and belts 150 and 152 is provided so as to passabout a somewhat similar arrangement of guide rolls, whereby the light,sensitive material-is carried from the discharging end of the developingchamber through the Ventilating chamber and is finally dischargedthrough deflectors 154 and 156 to the exterior of the cabinet at thefront of the machine. In this instance, the guide roll 158, about whichthe belts pass, is driven directly from a sprocket 160, about which achain 162 passes, which chain is driven from the cylinder sprocket 94.

One of the novel features of my present invention resides in theprovision of a cradle or receptacle, into which the light, sensitivematerial, such as strips or sheets of paper is discharged from thecabinet. In the present instance, this receptacle is constructed andarranged so as to assist in removing the occluded gases in the paper. Tothis end I provide a sheet metal cradle 164, which has spaced apartwalls to vprovide a hollow interior 166; the upper curvilinear wall 168,of-

this cradle is provided with a series of slots or perforations 170.which are particularly co-extensive with the inner upper wall of thereceptacle, and this receptacle is provided at one end with a connection172, with a suction fan, preferably suction fan 144, a1- though aseparate suction fan may be used, if desired. By reason of thisconstruction, when the light sensitive material is discharged into thecradle or receptacle, it is at once subjected to the drawing action ofthe air, which is sucked through the slots 170, so that the occludedammonia gases are pulled out of the paper and removed through theconduit 172.

In addition, the cylinder shown inFigjl,

in the drawing ibs provided with means for adjusting the blanket, sothat it will not come out of registration with the cylinder. To thisend, I provide a pair of bell-crank levers 40, at each end of the widthof the cabinet, which bell crank levers are pivotally mounted as thesprocket 42 in the 11p-standing bracket 24. One of the arms of each ofthese bell crank levers 40, to wit, 174, carries a bearing 176, in whichislrotatably mounted one of the arms of each of these bell crank levers40, to wit, 174, carries a bearing 176, in which bearings are mountedtwo nuts of ,the shaft carrying the guide roll 34.

In addition, these bell crank levers 40, are provided with lateralextending arms 178, connected by means ofsprings 180 to arms 182,pivotally mounted as at 184 to support 72, and each arm 182, is in turnprovided with an adjustable stop consisting of a screw 186, threadingthrough a lug 188, whereby when screws 186 are adjusted, the positionsof the respective arms 182 are altered and the tension of the springs180 is adjusted. A tripping lever 190, is pivotally mounted on part 192on the support and the inner end, 194, of this lever underlies thespring connected end of each of the levers 178, there being two of thesetripping levers, the same are in turn connected by means of relativelylong links 196, to another lever 198, connected to a cross shaftextending the width of the machine, which cross shaft has intermediateto its length a pedal 202, whereby, when the pedal is operated, thetripping lever 190 is actuated to raise the toe 194 thereof, and toraise the bell crank lever arm 178, whereby it throws the roller 34inwardly and e releases tension of blanket 28. Normally, this blanket ateach end is under the tension of the springs 180, which may be adjustedto produce a correct alignment of the blanket as it travels about .theguide rolls and cylinder. By reference to Fig. 1, it will be seen 'thatat the junction between the feed roll 36 and the cylinder, and the feedroll 32 and the cylinder, there is a space approximately {th to gth ofaninch between the felt roller and the blanket. Roll 36 carries asprocket gear, being driven by the chain. As soon as the operatorpresses upon the pedal 202, link 196 will be pulled down, which willraise toe 194 to shift lever arm 178 upwardly. thus releasing thetension on the guide roll 40 carried by the arm 174. As soon as thetension of the blanket is relieved through the normal movement of roller40, the chain 22 pulling on the roller 36 while running, will naturallydrive the blanket forward and cause the same to sag downwardly as shownin the dottedl lines; thus, the ltension between the blanket and thefelt roller is relieved and paper can be adjusted to any positiondesired.

By reference to Figures 8 and 9 of the drawings, I have shown aconstruction adapted to the modifications shown in Figure 4 of thedrawings wherein the cylinder 80 is driven, and b this contact with thecords or springs or be t 86 serves to drive the latter. Figure 8 showsthe manner of releasing the paper between the cylinder 204 and therelatively small belts or strings 206. In this instance, the cylinder204 is moved away from the belts or blanket 206. In this convstructionthe guide rolls 208 and 210 are mounted on a bracket 212 carried on theside of support 214. This bracket 212 has an upper arm 216 which isprovided with a semicircular branch 218 illustrated with dotted lines,which is fastened to the support 214 through a pivotal point 220. Inaddition, this pivotal axis 220 forms a pivotal point for a dependingarm 222 carrying at each end a bearing 224 for the cylinder shaft 226.The

support 214 is provided with a lug 228 through which passes a screw 230adapted to engage the pivotally mounted arm 222 for adjustment purposes.There are two of these arms and two of these adjusting screws, one foreach end of the cylinder shaft 226. By this means each end of thecylinder is kept in correct alignment with the traveling blanket, cardsor belt. In addition, thedower end of each arm 222 is connected by meansof a spring 232 with any stationary part of the support 214, in thisinstance, connected to a bearing for the guide roll 234, around whichthe cords or blankets or small belts pass. In addition, the support haspivotally mounted thereon as at 236, the bell crank lever 238 having atoe 240 adapted to shift into contact with the lower end of thepivotally mounted depending arm 222. The opposite end of the bell cranklever 238.has connected to it the link 240. Each one of these linksconnects to a lever arm similar to lever 198 shown in Figure 1, at thegear portion of which pedal 202 is connected. In the operation of thisdevice when the pedal is depressed the pivotally mounted depending arm222 is forced forwardly and upwardly to shift the'bearings 224 of thecylinder shaft away from the traveling cords or belts or blanket 206,whereby the paper may be adjusted or released. In addition, the bearingsfor the roller 234 are pivotally mounted as at 242 at each end thereof,and these'bearings are provided-with a lateral flange carrying-lat eralfiange 236, each carryin an adjusting screw 238, whereby each en of theguide roll 234 may be adjustedto keep the belt in ali ment with thecylinder.

iilFigure 9 the cylinder 246 is mounted in bearings 248 at each endthereof, which bearings are pivoted at 250, and two arms 252 areconnected by means of springs 254 to the stationary-support 256, so thatthe cylinder is normally pressedl against the travelin cords or blankets258 which pass around 51e various guide rolls 260. In addition, a bellcraiik lever 262 is pivoted at 264 to support 256 and a link 266connects withI the foot pedal as before, there being two bell cranklevers 262 and two link arms 266 as hereinbefore described, whereby whenthe lever is depressed the shaft 248 of the cylinder 246 is raisedupwardly from the traveling blankets to release the paper and permititsadjustment. In this construction, the guide roll 268, around which thebelts or blanket or cords travel, is pivotally mounted at 270, andcarries at its outer end 272, an adjusting screw 274, which may beadjusted to regulatey each end of the shaft 268, there being one suchadjustment at each end of the shaft to regulate the alignment of thisbelt relatively to the cylinder.

It will thus be seen that I have provided a very compact andcommercially operative developing apparatus wherein either sheets orstrips of light sensitive material may be fed through interruptedly orin a continuous :manner through the cabinet wherein they are subjectedto the sequential developing and degassing operations. In the developingoperation the pure ammonia gas is projected in a thin sheet againsteither the traveling blanket or the traveling cylinder, or both, oragainst the light sensitive material itself, while at the same time thematerial is continuously passed through the developing chamber., Inaddition, by means of the packing strips 46, located both at the inletand discharge openings of the cabinet, the gas is prevented fromescaping to the atmosphere. The particular details of construction ofthe valve mechanism for discharging the gas in sheet form against thetraveling blanket is particularly adaptableto my improved type ofconstruction, since it permits of the control of this gas discharge fromthe exterior of the machine where the operator is not subjected to thegaseous fumes, and also in a 4 manner which permit of the exact andminute regulation of the volume of gas discharged. Also, by thearrangement of this gas discharge in combination with the porous blanketor cylinder, I am enabled most effectiyely to procure a quickdevelopment of the light sensitive material and without wetting thesame, thereby endangeringthe light sensitive material due to the usualbleeding or warping. Also, by the arrangement of my improved ventilatedchamber and the manner in which the light sensitive material isdischarged from the blanket and cylinder into the traveling belts orcords and carried through the Ventilating chamber, and also in my newarrangement of the discharge cradle or receptacle for receiving theultimately developed paper, and which cradle is provided with means forremoving the occluded gases, I am enabled to develop the paper in aminimum time and free from obnoxious developing gases.

It will thus be seen that I have .also provided a novel type of meansfor releasing the little belts, cords or the blanket from the cylinder,and this means also includes various modifications for accomplishingthis and also for accomplishing the alignment of the travcling cords,belts or blanket with respect to the cylinder.

It is thought that the invention and numerous of its attendantadvantages will be understood from the foregoing description and it isobvious that numerous changes may be made in the form, construction andarrangement of the various parts of the apparatus disclosed withoutdeparting from the spirit and scope of my invention or sacrificing anyof its attendant advantages, the form hereinbefore described being apreferred embodiment for the purpose of illustrating my invention.

I do not claim herein any of the subjectmatter described and claimed inmy cepending application Serial No. 245,333, filed J anuary 9, 1928 forDeveloping apparatus with blanket adjustment and spray application ofliquid ammonia.

Having thus described my invention what I claim as new and desire tosecure by Letters Patent is:

l. In developing apparatus for light sensitive material, the combinationof an enclosing cabinet forming a developing chamber, means in saidchamber for feeding light sensitive material therethrough, and a tubularvalve located in said chamber and con- ,Y

nected to a source of ammonia gas, said valve being constructed andarranged to discharge a sheet of ammonia gas directly into contact withthe feeding means, and said feeding means having a porous surface toocclude the gases and to bring such occluded gases into contact with thesensitive side of the light sensitive material. f i

2. In a developing apparatus, the combination of a rotatable cylinderhaving a porous surface, means for projecting ammonia gas against saidporous surface and means for pressing the sensitive side of lightsensitive material to be developed against said porous surface and meansfor rotating the cylinder, whereby to develop said material as thecarrier travels, said ammonia projecting means comprising a tubularvalve arranged adjacent said cylinder and connected to a source ofammonia gas, said valve being constructed to discharge a sheet ofammonia gas directly into contact with the porous surface of thecylinder. j

3. In a developing apparatus, the combination of two carriers, one ofwhich is arotatable cylinder having a porous surface and the other ofwhich comprises a belt passing partially around the cylinder, means forintroducing light sensitive material between said carriers and intocontact with the porous surlla face of the cylinder, and means fooccluding ammonia gas in said porous surface so as to contact said gaswith the light sensitive material, said ammonia occluding meanscomprisinggan elongated valve comprising concentric tubes formed withslots, means for .relatively shifting the tubes to register said slotswhereby said valve may discharge a sheet of ammonia gas directly intocontact with the cylinder whereby the porous surface thereof may occludethe gas and means for rotating said cylinder.

4. In a device of the class described, the combination of anenclosingcabinet forming a developing chamber; means for feeding lightsensitive material therethrough, and means for projecting developing gasupon said feeding means comprising concentric hollow tubes, eachprovided with longitudi nal slots; means for I,rotating said tubesrelatively to cause said slots to register or to be adjusted out ofregistration; and means for connecting a source of ammonia gas to theinner hollow tube.

5. In a device of the class described, the combination of an enclosingcasing; means therein for feeding light sensitive material through thecasing; means for projecting ammonia gas in said casing comprising aninner hollow sleeve connected to a source of ammonia gas under pressure,and an outer hollow sleeve, said sleeves contacting through their lengthand having registrable slots longitudinally thereof and a handleconnected to the outer sleeve for turning the latter and means forholding saidsleeves in adjusted position.`

6. In a device of the class described, the combination of a developingcasing, means for feeding light sensitive material through said casingto develop the same, a ventilated casing adapted to receive the lightsensitive material discharged from said developing casing, means. forconveying the light sensitive material through said Ventilating casing,means for sucking a column of air through said Ventilating casing, areceiving trough at the discharge end of said ventilated casing, saidreceiving trough being hollow and having its upper surface provided witha plurality of openings and a suction line connected with a hollowtrough, said perforated upper surface-of the trough being constructedand arranged to receive the discharge from the ventilated casing.

7. In a device of the class described, the combination of a cabinetforming a developing chamber, a trough adapted to receive the dischargefrom said cabinet; means for feeding light sensitive material throughsaid developing chamber and for discharging it from the cabinet; meansin said developing chamber for subjectin the 1i ht sensitive material tothe action o ammonia ases, said trough being provided with a per oratedreceiving surface and said perforated surface being connected to asuction exhaust whereby to suck occluded gases from said light sensitivematerial as it rests upon the trou h.

8. In a device of the class describe the combination of means forming adeveloping chamber having an outlet, means for liberating a chemicallyactive gas in said developing chamber, means for feeding light sensitivematerial through the developing chamber and through the outlet of thecabinet, and a hollow trough arranged to receive the light sensitivematerial, the upper surface of said trough being foraminated and saidhollow trough being connected with a suction line.

'9. In a device of the class described, the combination of means forminga developing vchamber having an outlet, means for feeding lightsensitive material to the developing cabinet and through the outletthereof, means including an elongated tubular valve located in saidchamber for liberating a chemically' active developing gas therein and ahollow trough arranged-to receive the light sensitive material, theupper surface of said trough being foraminated and the trough beingconnected to a suction.

10. In a device of the class described, the combination of means forminga developing cabinet having openings for the insertion and "discharge oflight sensitive material from a cabinet, a pair of cooperating carriersmountasy ed in the cabinet, one of which is a rotatable cylinder and theother of which is a belt passing around the cylinder, whereby lightsensitive material may be fed along through the cabinet therebetween,means for feeding light ,sensitive material introduced through the inletopening between said carriers whereby the

